Optimus and Elita one always wanted a Sparkling but with the allspark destroyed and war going on it was to dangeruse. With the Allsparks destruction new life is hard as they are going to their own destruction. But that is what the bots belive as they have forgotten a energy like the Allspark can not be destroyed. It just changes form so when the autobots while scouting for a new location for their base that they fund the new spark.